Agar content of estuarine seaweed Gracilaria using different cultivation methods.

Red algae Gracilaria is one of the most cultivated seaweeds and a major source of agar in the world. Gracilaria demonstrates easy propagation, high growth rates, and tolerance to a broad range of salinities. Agar usage is related to thermo-reversible gels formation at low concentrations in water with wide applications in food, pharmaceutical, medical, engineering, agricultural and other fields. In this work, we analyzed and compared agar content of the estuarine seaweed Gracilaria sp. grown in two distinct cultivation methods: (1) inshore tank cultivation technique and (2) indoor cultivation technique using different mediums (seawater and brackish water) to get a better understanding about the best medium for large scale sustainable cultivation in the future; wild Gracilaria sp. samples were used as control. Inshore tank cultivation exhibited the highest agar extraction yield (20.67±0.27%) when compared with the control (16.67±2.72%); indoor cultivation using brackish water medium (13.8 ± 1.5%) and seawater medium...